Does early anorexia cause weakness and lightheadeness? what other physical symptoms does it cause? do the symptoms ease later on?

Anorexia-dangerous: It can be life-threatening. Anorexics often have problems with electrolyte balance which can have critical effects on the heart. Imbalance of fluids/nutrition, muscle wasting, toxic metabolites, not a healthy state of mind or body. The human body needs an optimal amount of hydration, nutrition, energy, & activity. Too much or too little is not a state of health, but rather a dangerous game.